good evening
I have a sony tv with google tv.
when I do a search for applications to install, it tells me that there are none, it only shows me results of movies or videos (first image)
If I do the search in google play, it returns results without problems (second image)
Probably because "flow" is just a too general word, so it doesn't know that you are looking for apps.
Try to actually tell it what you want. "Find flow in the play store" or "Install the flow app". That should work better.
But the voice system is kinda trash in general... So don't have too high expectations of it.